Weighing-scale.



No. 842,131. PATENTED JAN. 22, 1907. A. WMBARNARD.

WEIGHING SCALE. APPLIGAIION FILED 111:0. a, 1905. 7 SHEETS-SHEET 1.

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PATENTED JAN. 22, 1907.

A. W. BARNARD.

9 1 a o B B D m. mm N Gm IT A W0 I L P TPATENTED JAN. 22, 190'].

ITO-842,131.

A. W. BARNARD. WEIGHING SCALE. nrmm'non FILED DBO. a. 1905.

PATENTBD JAN. 22, 1907.

A. WVBARNA'BD. WEIGHING SCALE. APPLICATION FILED DEC. 8. 1905.

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m f 1/ M m W O 4 6 A. 5 8 7 6 W m 1 2 a Z3 0 R PATENTBD JAN. 22, 1907.

.A. w. BARNARD. vvgxenme SCALE. APPLICATION TILED DEC 8 190 PATENTBD JAN. 22, 1907.

A. W. BARN ARD. WEIGHING SCALE. APPLICATION FILED D30, 8. 1905.

-SHEET '7. ----95 WP w lIIlllIIllIT lnllilll "UNITED srA rEs PerENf'r orr on.

ARTHUR WV. BARNARD, OF NEWTON GENEH, MASSACHUSETTS, ASSIGNOK TO THE BARNARD COMPANY, OF BOSTON, MASSACHUSETTS, A COR- PORATION OF MASSACHUSETTS.

WEIGHING-SCALE.

Specification of Letters Patent.

I Patented Jan.22,19( )7.

Application filed December 8, 1905. Serial No. 290,902.

In alt whom it mwy-comcern:

'Be it known that I, ARTHUR W. BARNARD, -a'citizen of theUnited States, residing at ,Newton Center, in the county of Middlesex and State of Massachusetts, have invented a new and useful Improvement in Weighing- Scales, of-which the following is a speciiication, reference being had therein to the accompanying drawings.

.My invention relates to certain new and useful improvements in Weighing-scales gen-.

erally, and is hereinafter shown and described as appliedparticularly to that class of-weighing-scales' whereon the weight and selling price of a commodity are shown without requiring any mental calculation on the part of. the weigher.. Heretofore this class of scales has been operated by springs, the use of which, owingto the fact that the tension of springs is changed by variations in temperature, long use, and other conditions, has

' vmade it practically impossible to produce a scale which will remain accurate for any con .siderable period of time. Furthermore, in drum-scales where two springs are employed;

one on each side of the drum, there is a eonstant change i'rom long and continued use in the tension of each spring, and as these changes are not generally equal in the two springs there is a consequent tilting oi the equalizing-bar when the scale is' operated, which further tends to make theseale inaccurate. Maiigy devices have been constructed for such scales for the purpose ofcompensating for the variation in the tension of the springs due to change in temperature;

but no device has yet been made which will compensate for the change in the springs due to continued use, and therefore it becomes necessary to readjust such scales from time to time to make up for the t'ensional change in the springs.

OtllGI' conditions, and I. accomplish this re- The object of my invention is to provide a scale which is always uniform and accurate and which is not affected by changes in temperature, long and continued use, or any suit by discarding the springs now used in such scales andsubstituting therefor a pendulu'in device. In this connection I. have found it necessary to provide means whereby the pendulum will always move the same distance to indicate a given weight. In cases where a pendulum is used for operating a scale and weight is indicatedby the movement of the pendulum it has been found that the force required to swing the pendulum upwardly from a vertical position toward a horizontalpositioii does not increase in proportion to the length of the are through which it is swung, but increases at certain points much more rapidly than at other points that is, the force required to swing a ionduluni upwardly from a vertical to a 101izontal position shows a variable and not a constant increase. For this reason where the'pendulum is connected to a dial and the hand on the dial is movedin proportion to the movement of the pendulum it has been necessary to mark the dial with graduai lODS of varying size to correspond to the For instance,

movement of the pendulum. a force of one pound might move the pendulum to one side from a vertical position through an arc of ten degrees, whereas if the pendulum was in an oblique position the same force applied would move it through an arc of only two or three degrees. Therefore the use of a pendulum in the place of springs would involve a marking of the indicating drum or dial with graduations of varying size to correspond with the movement of the pendulum; but as it is preferable for the sake of accuracy to have the drum or dial marked with equal graduations 1 provide means which compensate for the variable move-.

ment of the pendulum and cause the pendulum to move in proportion to the weight.

, Broadly, my invention comprises a scale in which the beam is operated by a pendulum,

together with indicating means opcratively connected to the scale-beam and, means whereby the pendulum is moved uniformly;

Althoughmy invention is herein shown as applied to a drum-scale, yet I do not wish to limit myself to that class of scales, as my invention with slight changes, of construction may be adapted to other terms of scales than that illustrated in the drawings In the draw1ngs,which illustrate my device applied to one l'ermiii scales, and in which similar numbers rolerft o similar parts throu gh out the several views, Figure 1 is a front view in perspective of a scalermbodying my invention. Figj 2 is a rear'view in perspective oi the same. Fig. 3 is al'ront elevation of the same. Fig. 4. is a side elevation. Fig. 5 is a vertical sectional view on line 5 5 in Fig. 6. Fig. 6 is a longitudinal vertical sectional view on line 6 6 in Fig. 5. Fig. 7 is an end elevation of a detail. Fig. 8 is a side elevation of the same. Fig. 9 is a vertical longitudinal sectional view of the regulating device on line 9 9 in Fig. 10. Fig. .0 is a side elevation of the regulating device. Fig. 11 is a front elevation,partly in section, of the upper portion of the pendulum and mechanism in the rear. Fig. 12 is a side elevation of a portion of a bar provided with knife-edges, and Fig. 13 is a transverse sectional view of the same on line- 13 1;) in Fig. 12. Fig. 14 is a side elevation of the plunger device, which regulates the movement of the pendulum, the same being locked. Fig. 15 is avertical sectional view of the plunger device, the plunger being shown in a depressed position. Fig. 16 is a view, partly in side elevation and partly in section, of the plunger device, the plunger being shown in a raised position; and Fig. 17 is a cross-sectional view of the plunger device on line 17 17 in Fig. 15.

in applying my invention to the form of scale hereinafter described and illustrated I retain many features of construction which are old and well known inthe scale art. The new features, which are described in detail hereinafter, are briefly as follows: I provide a pendulum properly mounted and operatively connected to the scale-beam to offset the weight upon the scale-platform. To regrelate the movement of said pendulumand cause it to swing in proportion to the weight on the scale-platform, a plunger device is provided and so'mounted that it will offer a resistance to the movement of the pendulum just su'fiicient to overcome the variations in its movement and cause the pendulum to move unifori'nly. Further, the mechanism operating the indicating device is mounted upon and SUDPOItHlbYthG endof the scale.

beam in such manner that when the scalebeam is depressed by weight the operating mechanism tollows it downwarily, thus preventing the lost mctionflvhichis always present to a greater or less degree in scales where the indicator-operating mechanism is supported otherwise and is operated 'by' being pulled by the scale-beam against spring or other tension.

In the first place my method of adapting the pendulum to the l'ierein-described form of scales is as follows: In the drawings, 1 represents a platform supported on a frame 2, which in turn is supported upon kniieedge bearings 3 on a beam 4, pivoted on knife-edge bearings 6 on a standard 5 on a base 7. said beam 4 being provided with an equalizing or balance weight 8 on its forward end. The downwardly-depending rod 9, fixed to the frame 2, is pivotally attached at its lower extremity to a check-bar 10, the

latter being pivotally connected to a depending lixed bracket 11, said rod and checkbar serving to keep the platform 1 horizontal when the beam 4; is moved. The beam 4 is loop-shaped, having its two' ends 12 extending rearwardly and the loop portion turned toward the front of the scale. 14 is a platform guard or grille. All of the foregoing is 01 ordinary and well-known construction. For the purpose oi coun'terbalancing tl'ie'wcight on the scale-platform I provide a pendulum 15, hung on a spindle 17, which rotates on knife-edge bearings 18 between standards 19, which rise irombase 7. This pendulum 15 swings outwardly toward the 11 ont ol" the scale in a prescribed and limited arc. It will be noticed that in Fig. 6 the. pendulum is shown as hanging a trifle out or the vertical, which is caused by the weight of the mechanism on the scale-beam beingoltset by the pendulum. To connect. the pendulum 15 to the ends 12 of the scalebeam 4 in order to counterbalance the weight on the platform 1, the spindle '17 has fixedly mounted thereon a lever 20, extend.

ing rearwardly and upwardly, said pendulum,

spindle, and lever all beinglixcd in relation to I each other and all moving 'in unison: ;.T-hfe free end 21 of lever 20 is forked. and the fork carries a l nite-edge-bearing 22. -,The beamarms 12 1'2 areconnected by a cross-rod 3, provided with a centrally-disposed knil'eedge bearing 24. The lever 20 and the sale-arms 12 12 are connected. by a vertical rod 25, having on-each end a hook or loop 26, within which is mounted a bearing-sun ace 27, adapted to engage the knife-edges in the end or the lever 20 and on the crossgrod 23.. As the knife-edge- 22 is turned upwardly, the upper bearing 27 faces downwardly andthe knii'e-edge 24' between the beam-arms 12 is turned downwardly and engages the bearing 27, which is faced upwardly. Set-screws 28 serve to keep the knii'eeedges 22 and 24. from: jumping away from their bearings and out of the loops 26 when the scale is operated suddenly or jarred. The leve" 20 and thebeamauras 12 may b6 LiiSCODl'lGCttXl by unscrewing th sct sc-rews 2; and removing the rod 25. This construction is fully illustrated in Fig. 6.

The above method of adapting the endulum to the scale-beam may be app ied to other forms of scales without any essential changes in construction.

Arising from the base tirare standards 3.0 30, supporting a casing 31, within, which rotates a drum 34 of suitable form, adapted to carry a dial 35, suitably marked. This construction is also old and well-known in. the scale art. The said drum 34ismounted upon a shaft 36, which is journaled at each end in suitable bearings. The casing 31 has skeleton end plates 37, upon each ot-which is fastened a lug 38, to which-:is adjustably attached'a depending bracket 39, carrying a ball-bearing retainer iO, held by a set-screw.

I 41. Upon either end of shaft 36 is mounted loosely journaled in the lower part of the rack-bar 45', which expands to form a collar Upon one side of said collar is a transverse arm 53,,car'rying a ball or weight 54, which acts as a counterweight to tilt the rack-bar 45 forward and retain it in close en* 1 gagement with pinion 43.

To prevent lateral movement of the rack-bar 45 on the adjustment-rod 50, a collar 55, held by a setscrew 56, is placed on one side of the collar 51,

the latter abutting'on the other side against a plate, hereinafter described. (See Figs. 7 and 8.)

In the foregoing construction the drum is operated by the vertical movement of the rack-bars 45, the latter being operated by the scale-beam through the following-described means: At this point there is a radical difference between my scale and those heretofore in use and operated by springs.

In the latter class of scales the drum has been rotated by the scale-beam pulling the rackbarsdownwardly against the tension of the springs." This mode of operation is, however,

, I open to the objection that there is always present a certain amount of lost motion. in

operate the drum. -When the scale-beam returns to its normal position, the drum-operating mechanism is pushed upwardly by the beam. By means of these changes I am enabl'ed" to eradicate all lost motion and to operate drum Whenever there is the slightest downward movement of the scale-beam.

This portion of my invention comprises a frame consisting of an upper longitudinal bar 60, having two depending rods 61, the

upper ends of which pass through the bar 60 i and are fiixedly secured thereto'by means of a shoulder 62 on each rod 61, which engages the under surface of the bar 60, and by a nut 63 on the end of each rod 61 on the upper I side of said bar 60.

rod 6 is split to form a fork 64, within which I The lower end of each is set a downwardly-turned bearing-surface 6.5, adapted to rest upon a knife-edge 66, set transversely ln the end of the scale-arm 12.

The rods 61 are so placed as to include between them the scale-beam ends '12 12. About nndwaya transverse bar 67 connects thc'two rods 61 and serves to hold them in position and in addition to carry the pluni,

ger and (lash-pot mechanisms. The frame just described is so disposed as to move in the same vertical plane. with the; rack-bars 45 and ad ustmentrod 50. R'lo-secure this 1 movement in the same plane, upon each end of the bar is fixed an upwardly-extending i ably mounted upon end casings 37, the ob ject of this construction being to retain said frame at all times in a perpendicular position, and thereby prevent any swinging movement. In order to adjust the said frame and the adjustment-rod 50 to each other, I provide the following device, although for this purpose any suitable means may be employed, since it is not one of the novel fea' tures of my invention. In the center of the adjustment-rod 50 is mounted transversely a rectangular'link 76, having its horizontal sides beveled .to form knife-edge contacts 77 with theadjustment-rod. (See Fi s. 9 and 10.) The rectangular form of the dink permits of a limited horizontal movement. From the lower side of this link is a downwardly-extending lug 78, loosely engaging'a bore 79 in the rod 60. The latter at this point is provided with an extension 80 on its screw-nut 81', which regulates the position of the adjustment-rod 50, the lower end of the lug 78 resting upon the point of said screwnut 81.. A set-screw 82 engages the lug 78 adjustment. 1 enabled at all times to raise or to lower the drum-operating mechanism in relation to the bar 60 and frame, which is supported by the scale-beam, and thereby regulate the relation of dial and scale-beam.

In Figs. 12 and 13 is shown, on an enlarged scale, a knife-edge of identical form with knife-edges 22, signed especially to prevent any lateral movement of the knife-edge on the bearingsurfacc and to secure, this result without appreciable friction. In these figures, 85 indicates the knife-edge, and 86 the rod on which the knife-edge is cut. Ordinarily the forming of a knife-edge in the bar 86 would result in transverse faces being formed on would tend to contact the side of the bearing-surface and cause friction. To avoid this, .l form an undercut shoulder or-projeel tion 87'at each end of the knife-edge, the point of said projection 87 cxtcnding'slightly 1 above the knife-edge, and thus forming a knife-edge point which engages the bearingsurface and prevents lateral movement without friction.

upright rod 72, held therein y screws 7 3 73.

60 between knife-edge bearings 74, adjustunder side in orderto receive and hold a to prevent it drawing out of the bore 79 after I By means -of this device I am 24, and 66, this form being de either side of the knife-edge, which faces I,

As heretofore explained, the pendulum is this device, like all pendulums, moves in an arc and requires a variably-increasing force to move it a unit of distance as it swings away from a vertical position. if this were not corrected, it would be necessary to mark the indicating device with graduations of various size; but in order to correct the irregular movement of the pendulum and cause it to move in regular steps in proportion to the weight l provide the following device, which is illustrated in detail in Figs. 14,- 15, 16, and 17. ()n the rear of the scale and directly under the frame I mount a hollow cylinder 90, open at the top and adapted to contain mercury M or other suitable fluid. 'lhis cylinder 90 has on its upper exterior surface a screw-thread 91., which engages a screw-threznl in the upper portion of the base 7 and permits the cylinder to be adjusted vertically in relation to the base of the scale. A check-nut 92 secures the cylinder in position after adjustment. To the top of the cylinder is screwed an upright tube 93 of a diametersmaller than that of the cylinder and provided on itsupper interior circum l'erence with a screw-thread 94. Depending from the cross-bar 67 and fixedly mounted thereon is a plunger-rod 95, carrying a plunger 96 and adapted to move upwardly and downwardly in said cylinder and tube 93 without contacting the sides thereof. The upper part of said plunger-rod 95 is provided with a screw-thread to carry a depend ing hood 97, which is of a diameter sufficient to inclose the tube 93 without contacting it. From the'interior underneath surface of the top of said hood is a circular flange 98, having a'stuew-thread on its outer circumference which is adapted to engage the screw -thread 94 on the tube 98. Nhen the apparatus is being moved or transported, the hood 97 is screwed down and the llange 98 closes up the tube 93, which pre vents the mercury or other liquid in the cylinder from leaking out. in Fig. 14 the device is shown locked and ready for transportation.

in Fig. the plunger is shown in alowermost. position and in Fig. 16 in itshighcst position. lhe shape of the plunger is a very unportant consideration, as the plunger must be of such form that it will exactly compensate for the otherwise variable move ment of the pendulum, and therefore cause it to move uniformly. By uniform movement as applied to the pendulum I mean that a given weight will always move the pendulum a given distance irrespective of the position of the pendulum when the given weight is applied. Thus a weight oi one pound will always cause the pendulum to move through a certain arc, whether the pendulum be hany ing vertically or be in a raised position when the weight is applied.

it has been demonstrated by experiment that in the form of scales herein shown and with. the same arrangement and relation of" the various parts thereof the plunger should be of the shape herein illustrated; but the form ofthe plunger will depend upon various details of construction obvious to those skilled in the art.

To reduce the oscillations of the scalar beam, a dash-pot device of any ordinaryeon struction may be mounted on the rear of the scale beside the plunger device. In the dash-pot shown in the drawings, 105 is the cylinder containing a liquid, 106 asc-rew-top, 107 a tube extending upwardly from said top, and 10h a hood attached to the cross-rod 67 to prevent the entrance of dust or dirt into the cylinder. The interior construction is similar to the ordinary (lashpot, and the piston-rod is attached to the cross-rod 67.

In operation my invention works simplyand efliciently. Vhen the article to be weighed is placed upon the platform 1, the latter is depressed and the scalenrms 12 12 move downwardly and through the medium of the rod and lever 20 swing the pendu him 15 outwardly and upwardly until it counterbalances the load on the platform. The knife-edge bearings at the various points of contact reduce the friction to a minimum. As the scale-arms 12 12 are depressed by the load on the platform the frame composed of bars and 61, together with the drum-0perating mechanism, all being supported upon the scale-arms 12 12, drops with them and thereby operates the drum. as they move downwardly turn the pinions 43, and thereby rotate the drum 34, which' carries the dial. At the same time the plunger 96 is forced downwardly into the mercury M, which offers anadditional resistance to the depression of the scale-arms under the load. When the scale-beam is evenly balancedthat is, when there is no load upon the platform 1 and the dial is at zerothe point of the plunger fi should just penetrate the surface of the mercury in the cylinder 90. In this connection I prefer to use mercury, since its high specific 'ravity enables me to use a much smaller plunger than would be' required if glycerin or other similar liquid" were employed. 1 have heretofore explained that the pendulum 15 when not operated in connection with, my plunger device under the influence of uniform increments to the weight upon the scale platform or pan moves through successively shorter arcs. A uniform increment to the weight on the scaleplatform or scale-panadds a diminishin increment to the are of travel of the pendu um.

I have postulated the requirement that the 1 pendulum shall move through equal arcs for equal increments to the weight on the scalepen, and in order to accomplish this I have provided the plungerdeviee, which renders the incrementsto the are of travel of the pen- I dulum uniformly proportional to increments on the weight on the scale-pan.

Laying aside the actual construction of the machine, it will be observed that its principle is founded upon the fact that the submergence of the plunger is by increments intended to oil'set the decreasing increments to the are of travel of the pendulum. It is to beobserved, of course, in a practical embodiment of the device the weight and arrange- ,ment of the parts, the varying ellieiency ol the'dial at zero by "means of the regulating device connected to adjustment-rod and rod 60. Then, for example, a ten-pound weight is placed on the platform, and if the dial registers more than ten pounds thecylinder .90 is raised in order that theplunger 96 may be immersed to a greater extent. if, (in the contrary, the dial shows less than ten pounds, the cylinder is then lowered until the dial registers exactly ten pounds. When ,the cylinder has been so adjusted, then the seale is correct and remains so. untildisturbed ,bv accident or otherwise.

The present invention is not limited to the embodiment illustrated in the drawings; but

" it may be embodied in other and widely-different forms.

Where in the followingclaims l have emplunger device, I have intended to define a construction employing a part adapted to be submerged more and more as the pendulum is raised irrespective of the particular form of such device. I

What 1 claim is 1 1.v Aiscale, having in combination, a scalepan', a pendulum counterbalanee and a cortiona to the weight on the rec ting device connectedtherewith to cause said endulum to move through arcs proporscale-pan; said correcting device comprising .a receptacle containing liquid anda submersible member.

2. In a scale, the combination of a scalepan, an automatic counterbalancing device, and a plunger device to cause said counterbalancmg device to move a distance proportional to the weight on the scale-beam; said plungerv device consisting of a receptacle con.

taining liquid and a submersible member.

3. 1n a scale, the combination of a scalebeam, counterbalancing means operatively connected to said scale-beam, and a plunger device to causesaid countcrbalancing means to move in equal stops when equal increments of weight are placed on the scale-beam; said plunger device comprising a receptacle containing liquid and a submersible member.

4. in a scale, the combination of a scale. beam, a pendulum operatively connected theretb, -and a plunger device whereby the endulum is caused to move a distance proportional to the weight on the scale-beam; said plunger device comprising a receptacle con'tannngliquid and a submersible member.

5. in a scale, the combination of a pendu lum, weight-indicating means, and a plunger device to cause said pendulum to'move a 01s tance proportional to the weight applied;

said plunger device comprising a rcceptacleifiei containing liquid and a submersible member. 6. .111 a scale, the combination of a scalebeam, a pendulum operatively connected thereto, indicating means, and a plunger device to cause said pendulum to move a distance proportional to the weight on the scalebeam; said plunger device comprising a receptacle contalmng liquid and a submersible member.

7. The combination of a scale-beam, a-

pendulum 'operatively connected to said beam, an indicator, means whereby said in- (heater is operated by said beam, and a plunger device to' cause said pendulum to move'a distance proportional to the weight on the scale-beam said plunger device comprising a receptacle containing liquid and a submersible member.

8. in a scale, the combination of a scalebeam, a pendulum, means connecting said pendulum and said scale-beam whereby the vweight on the scale-platform is counterbalanced by said pendulum, and a -plunger device to cause said pendulum to move in proportion to the weight on the said scale-plat form; said plunger device comprising a wee tacle containing liquid and a submersib e member.

9. The combination of a scale-beam, a pendulum operatively eoimected to .said scalebeam, a rotatable drum provided with a dial, means to operate said drum, and a plunger device to cause said pendulumto move in proportion to the weight; said plunger device com prising a receptacle containing liquid and a submersible member.

10. in a scale, the combination of a scalebeam, a pendulum operatively connected to said scale-beam, a rotatable drum provided with a suitable dial, means whereby said-v said scale-beam, a drum carrying a dial,.

means whereby said drum is operated by ICC said scale-beam to indicate the Weight and price of the object being weighed, and a plunger device to compensate tor the otherwise variable movement ol said pendulum; said plunger device comprising a receptacle cont-aimng liquid and a submersible member.

12. in a scale, the combination 01 a scale beam, a pendulum operatively connected to said scale-beam, a rotatable drum to indicate end of said scalebcam to operate said drum,

and means to compensate for the otherwise varia ble movement ol" said pendulum and to cause said pendulum to move in equal steps when equal increments of weight are placed upon the scale.

'14. In a scale, the combination of a scalebeam, a pendulum, means connecting said pendulum to said scale-beam, a drum, a frame supported on said scale-beam and provided with means to operate said drum, and means to compensate for the other ise variable movement of said pendulum and to cause said pendulum to move in equal steps when equal increments of weight are placed upon the scale.-

'15. in a scale, the combination of a scalebeam, a pei'ioulum fixedly mounted 'upon a spindle which rotates in suitable bearings, a lever also mounted upon said spindle and having its free end connected tothe scalebeam, a drum rotatably mounted on a shaft and suitably marked to indicate weight and price, said shaft, a spindle mounted on each end of said shaft, racliz bars enmeshing with said spindles, a rod connecting said rackbars, a frame supported on said scale-beam, adjustable means connecting said rod and said frame, and means to compensate for the otherwise variable movement oi said pendulum and to cause said pendulum to move .in equal steps when equal increments of weight are placed upon the scale.

is. In a sea e, the combination of a scalebeam, a pendulum operatively connected thereto, arotary drum carrying a dial to indicate weight and price, operating means, a

frame{supported on the end of said scalebeam and carrying sithl operating means,

means lo. adjusting the relation of said operating means l-ilil said .l'ranie to each other, a vertically-adjustable cyliuicr anaptcll to contain i'nercury or other suitable liquid, and plunger suspended lnnn sail theme and adapted. to be llllll'lQI'SOll in sail liquid when the scale-beam is depressed tion of said plunger being such that it comlillt configura- 1 pensates for the variation in the movement I of said pendulum and causes it to move in equal steps when equal increments of weight are placed upon the scale.

beam, a pendulum device operatively connected to the said scale-beam to'counterbalance the load thereon, a rotary indicator provided with pinions, rack-bars enmeshing with said pinions, a frame supported on the connecting said rack-bars to said frame and a plunger novice to cause said. pendulum device to move in equal steps when equal in crements of weight are placed upon the scale.

18. In a scale, the combinationof a scalebeam, a pendulum mounted insuitable bearings and operatively connected to said scalebeam, a rotary indicator, pinions on the shaft of said indicator, raclebars enmeshing with said pinious, a frame supported on knifeeuge bearings upon the end of said scalebeam, said Knife-edge bearings and adjust able means connecting said rack-bars and said frame.

beam, coiuiterbalancing means operatively connected to said scale-beam, andineans to cause said counterbalancing means to move in equal steps when equal increments of weight are placeu on the scale; said means consisting of a cylimier containing mercury or other suitable liquid, a plunger, and means to adjust said cylinoer in relation to said plunger.

20. in a scale, the combination of a pendulum and a plunger device to cause said pendulum to move in equal steps when equal increments of Weight are placed uporrthe scale; said plunger device comprising a receptacle containing mercury or other suitable liquid and a plunger, having a variable cross-section, suspended from above and adapted to move up and down in said liquid.

21. in a scale, the combination of a scale beam, a pendulum operatively connected thereto, and a plunger device to cause said pendulmn to move in equal steps when equal increments of weight are placed upon the scale; said plunger device consisting of a re ceptacle. containing mercury or other suitable liquid and a submersible member, having a variable cross-section and suspended from the said scale-beam.

2'3. In a scale, the combination of a pen- (illllllll and a plunger device to cause said pemlulum to swing uniformly; said plunger device consisting of a cylinder containing mercury or other suitable liquid, and a plunger suspended from the scale-beam and adapter to move up and down in said liquid; the configuration of said plunger being such that the resistance of the liquid exactly compensates for the variation in the movement of the said pendulum and causes it to move 17. In a scale, the "combination ol a scaleend of said scalebeam, adjustable means 19. in a scale, the combination of a scale 

